Analog Devices,inc.

Gaurav Vohra

Xin Zhang

William Albert Clark

Michael W Judy

Jinbo Kuang

Mehrnaz Motiee

John Albert Geen

Thomas G O'Dwyer

Jeffrey A Gregory

Igor P Prikhodko

Isaac Chase Novet

Venugopal Gopinathan

YounJae Kook

A MEMS device is provided comprising a mass configured to move along a first axis and a second axis substantially perpendicular to the first axis; a drive structure coupled to the mass and configured to cause the mass to move along the first axis; a sense structure coupled to the mass and configured to detect motion of the mass along the second axis; a stress relief structure coupled to one of the drive structure or the sense structure; and at least one anchor coupled to an underlying substrate of the MEMS device, wherein the stress relief structure is coupled to the at least one anchor and the at least one anchor is disposed outside of the stress relief structure.

Drive and sense stress relief apparatus

A MEMS device is provided comprising a substrate; a proof mass coupled to the substrate and configured to move along a resonator axis; a drive structure comprising at least one electrode and configured to drive the proof mass to move along the resonator axis; and a pivoting linkage coupled to the proof mass at first and second ends of the pivoting linkage, the first end comprising a first fixed pivot and the second end comprising a second fixed pivot, the pivoting linkage comprising: a first bar configured to pivot about the first fixed pivot and a first dynamic pivot; a second bar configured to pivot about the second fixed pivot and a second dynamic pivot; and a third bar configured to pivot about the first dynamic pivot and the second dynamic pivot, wherein the proof mass moves along the resonator axis when the pivoting linkage pivots.

Stress-relief MEMS gyroscope

An impedance measurement system for detecting an analyte in a sample is disclosed. The system includes first, second, and third electrodes, wherein at least a portion of the third electrode is positioned between the first and second electrodes, means for generating an electromagnetic field between the first and second electrodes, means for electrically controlling the third electrode, wherein the third electrode modifies the electromagnetic field, and a processor for detecting a presence of the analyte in the sample, based at least in part on a property of the electromagnetic field.

Impedance measurement in diagnostic testing

Single-axis teeter-totter accelerometers having a plurality of anchors are disclosed. The plurality of anchors may be arranged about a rotation axis of the teeter-totter proof mass. Each of the plurality of anchors may be coupled to the proof mass by two torsional springs each extending along the rotation axis. The plurality of anchors allows an increased number of torsional springs to be coupled to the proof mass and thus greater torsional stiffness for the proof mass may be achieved. Due to the higher torsional stiffness, the disclosed single-axis teeter-totter accelerometers may be deployed in high-frequency environments where such increased torsional stiffness is required, for example, around 20 kHz and above.

Multiple anchor high frequency accelerometer

Z-axis teeter-totter accelerometers with embedded movable structures are disclosed. The teeter-totter accelerometer may include an embedded mass which pivots or translates out-of-plane from the teeter-totter beam. The pivoting or translating embedded mass may be positioned to increase the sensitivity of the z-axis accelerometer by providing greater z-axis displacement than the teeter-totter beam itself exhibits.

Increased sensitivity z-axis accelerometer

Capped microelectromechanical systems (MEMS) devices are described. In at least some situations, the MEMS device includes one or more masses which move. The cap may include a stopper which damps motion of the one or more movable masses. In at least some situations, the stopper damps motion of one of the masses but not another mass.

Vertical stopper for capping MEMS devices

Z-axis microelectromechanical systems (MEMS) accelerometers are described. The z-axis MEMS accelerometers are of a teeter-totter type, having a pivoting beam suspended above a substrate. A non-uniform gap distance between the pivoting beam and the substrate is provided to increase the sensitivity of the accelerometer to z-axis acceleration. In some embodiments, the non-uniform gap distance is created by one or more substrate layers, such as one or more layers of polysilicon on the substrate above which the pivoting beam is suspended. In some embodiments, the non-uniform gap distance is created by the use of one or more bumps on the beam. In some embodiments, both substrate layers and bumps are used to provide a non-uniform gap distance for different electrodes of the accelerometer. The non-uniform gap distance may include a gap of reduced height, resulting in increased sensitivity of the accelerometer to z-axis accelerations.

Z axis accelerometer using variable vertical gaps

Various embodiments mitigate the risk of frequency-lock in systems having multiple resonators by dynamically changing the frequency at which at least one of the resonators is driven. More particularly, the drive frequency of at least one of the resonators is changed often enough that the multiple resonators do not have time to achieve frequency lock. Changes in the oscillation of the resonators may be analyzed to determine, for example, acceleration of such systems. Some embodiments implement self-test by assessing expected performance of a system with toggling drive frequencies. More particularly, some embodiments implement self-test by artificially inducing displacement of a movable member of a system.

Method and apparatus for driving a multi-oscillator system

A method of detecting motion provides a resonator having a mass, moves the mass in a translational mode, and actuates the mass in a given bulk mode. The mass moves in the translational and given bulk modes at substantially the same time and, accordingly, the resonator is configured to detect linear and rotational movement when moving and actuating the mass in the translational and given bulk modes. The method produces one or more movement signals representing the detected linear and rotational movement.

Method and apparatus for detecting linear and rotational movement

Methods and apparatus for sensing linear acceleration with a MEMS resonator mass, alone, or concurrently with sensing rate of rotation. A resonator mass, which may be a disk or a ring structure, is driven at a resonance frequency of one of the vibration modes of the resonator mass. The amplitude of vibration of that mode is sensed by a set of at least two drive-sense electrodes disposed at opposing positions across the resonator mass. A linear acceleration is derived based at least on a difference between signals of the opposing electrodes. Linear acceleration may be sensed in multiple orthogonal dimensions using multiple pairs of opposing electrodes. Rotation rate may be derived concurrently by sensing the energy coupled into an orthogonal mode of the resonator mass.

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Sudbury, MA, United States of America

Gaurav Vohra